simgear/scene/sky/cloud.cxx

   1 // cloud.cxx -- model a single cloud layer
   2 //
   3 // Written by Curtis Olson, started June 2000.
   4 //
   5 // Copyright (C) 2000  Curtis L. Olson  - http://www.flightgear.org/~curt
   6 //
   7 // This library is free software; you can redistribute it and/or
   8 // modify it under the terms of the GNU Library General Public
   9 // License as published by the Free Software Foundation; either
  10 // version 2 of the License, or (at your option) any later version.
  11 //
  12 // This library is distributed in the hope that it will be useful, but
  13 // WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 // General Public License for more details.
  16 //
  17 // You should have received a copy of the GNU General Public License
  18 // along with this program; if not, write to the Free Software
  19 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  20 //
  21 // $Id$
  22
  23 #ifdef HAVE_CONFIG_H
  24 #  include <simgear_config.h>
  25 #endif
  26
  27 #include <simgear/compiler.h>
  28
  29 #include <sstream>
  30
  31 #include <math.h>
  32
  33 #include <osg/AlphaFunc>
  34 #include <osg/BlendFunc>
  35 #include <osg/Geode>
  36 #include <osg/Geometry>
  37 #include <osg/Material>
  38 #include <osg/ShadeModel>
  39 #include <osg/TexEnv>
  40 #include <osg/Texture2D>
  41 #include <osg/TextureCubeMap>
  42 #include <osg/TexMat>
  43
  44 #include <simgear/math/sg_random.h>
  45 #include <simgear/debug/logstream.hxx>
  46 #include <simgear/scene/model/model.hxx>
  47 #include <simgear/math/polar3d.hxx>
  48
  49 #include "newcloud.hxx"
  50 #include "cloudfield.hxx"
  51 #include "cloud.hxx"
  52
  53 // #if defined(__MINGW32__)
  54 // #define isnan(x) _isnan(x)
  55 // #endif
  56
  57 // #if defined (__FreeBSD__)
  58 // #  if __FreeBSD_version < 500000
  59 //      extern "C" {
  60 //        inline int isnan(double r) { return !(r <= 0 || r >= 0); }
  61 //      }
  62 // #  endif
  63 // #endif
  64
  65 #if defined (__CYGWIN__)
  66 #include <ieeefp.h>
  67 #endif
  68
  69 static osg::ref_ptr<osg::StateSet> layer_states[SGCloudLayer::SG_MAX_CLOUD_COVERAGES];
  70 static osg::ref_ptr<osg::StateSet> layer_states2[SGCloudLayer::SG_MAX_CLOUD_COVERAGES];
  71 static osg::ref_ptr<osg::TextureCubeMap> cubeMap;
  72 static bool state_initialized = false;
  73 static bool bump_mapping = false;
  74
  75 bool SGCloudLayer::enable_bump_mapping = false;
  76
  77 // make an StateSet for a cloud layer given the named texture
  78 static osg::StateSet*
  79 SGMakeState(const SGPath &path, const char* colorTexture,
  80             const char* normalTexture)
  81 {
  82     osg::StateSet *stateSet = new osg::StateSet;
  83
  84     SGPath colorPath(path);
  85     colorPath.append(colorTexture);
  86     stateSet->setTextureAttribute(0, SGLoadTexture2D(colorPath));
  87     stateSet->setTextureMode(0, GL_TEXTURE_2D, osg::StateAttribute::ON);
  88
  89     osg::TexEnv* texEnv = new osg::TexEnv;
  90     texEnv->setMode(osg::TexEnv::MODULATE);
  91     stateSet->setTextureAttribute(0, texEnv);
  92
  93     osg::ShadeModel* shadeModel = new osg::ShadeModel;
  94     // FIXME: TRUE??
  95     shadeModel->setMode(osg::ShadeModel::SMOOTH);
  96     stateSet->setAttributeAndModes(shadeModel);
  97
  98     stateSet->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
  99     stateSet->setMode(GL_CULL_FACE, osg::StateAttribute::OFF);
 100
 101 //     osg::AlphaFunc* alphaFunc = new osg::AlphaFunc;
 102 //     alphaFunc->setFunction(osg::AlphaFunc::GREATER);
 103 //     alphaFunc->setReferenceValue(0.01);
 104 //     stateSet->setAttribute(alphaFunc);
 105 //     stateSet->setMode(GL_ALPHA_TEST, osg::StateAttribute::ON);
 106     stateSet->setMode(GL_ALPHA_TEST, osg::StateAttribute::OFF);
 107
 108     osg::BlendFunc* blendFunc = new osg::BlendFunc;
 109     blendFunc->setSource(osg::BlendFunc::SRC_ALPHA);
 110     blendFunc->setDestination(osg::BlendFunc::ONE_MINUS_SRC_ALPHA);
 111     stateSet->setAttribute(blendFunc);
 112     stateSet->setMode(GL_BLEND, osg::StateAttribute::ON);
 113
 114 //     osg::Material* material = new osg::Material;
 115 //     material->setColorMode(osg::Material::AMBIENT_AND_DIFFUSE);
 116 //     material->setEmission(osg::Material::FRONT_AND_BACK,
 117 //                           osg::Vec4(0.05, 0.05, 0.05, 0));
 118 //     material->setSpecular(osg::Material::FRONT_AND_BACK,
 119 //                           osg::Vec4(0, 0, 0, 1));
 120 //     stateSet->setAttribute(material);
 121
 122     stateSet->setMode(GL_FOG, osg::StateAttribute::OFF);
 123
 124     // OSGFIXME: invented by me ...
 125 //     stateSet->setMode(GL_DEPTH_TEST, osg::StateAttribute::OFF);
 126 //     stateSet->setMode(GL_LIGHTING, osg::StateAttribute::ON);
 127
 128 //     stateSet->setMode(GL_LIGHT0, osg::StateAttribute::OFF);
 129
 130     // If the normal texture is given prepare a bumpmapping enabled state
 131 //     if (normalTexture) {
 132 //       SGPath normalPath(path);
 133 //       normalPath.append(normalTexture);
 134 //       stateSet->setTextureAttribute(2, SGLoadTexture2D(normalPath));
 135 //       stateSet->setTextureMode(2, GL_TEXTURE_2D, osg::StateAttribute::ON);
 136 //     }
 137
 138     return stateSet;
 139 }
 140
 141 // Constructor
 142 SGCloudLayer::SGCloudLayer( const string &tex_path ) :
 143     layer_root(new osg::Switch),
 144     group_top(new osg::Group),
 145     group_bottom(new osg::Group),
 146     layer_transform(new osg::MatrixTransform),
 147     cloud_alpha(1.0),
 148     texture_path(tex_path),
 149     layer_span(0.0),
 150     layer_asl(0.0),
 151     layer_thickness(0.0),
 152     layer_transition(0.0),
 153     layer_coverage(SG_CLOUD_CLEAR),
 154     scale(4000.0),
 155     speed(0.0),
 156     direction(0.0),
 157     last_lon(0.0),
 158     last_lat(0.0)
 159 {
 160   layer_root->addChild(group_bottom.get());
 161   layer_root->addChild(group_top.get());
 162   // Force the cloud layers into recursive bins of bin 4.
 163   osg::StateSet *rootSet = layer_root->getOrCreateStateSet();
 164   rootSet->setRenderBinDetails(4, "RenderBin");
 165   rootSet->setTextureAttribute(0, new osg::TexMat());
 166   base = osg::Vec2(sg_random(), sg_random());
 167
 168   group_top->addChild(layer_transform.get());
 169   group_bottom->addChild(layer_transform.get());
 170
 171   layer3D = new SGCloudField;
 172   rebuild();
 173 }
 174
 175 // Destructor
 176 SGCloudLayer::~SGCloudLayer()
 177 {
 178   delete layer3D;
 179 }
 180
 181 float
 182 SGCloudLayer::getSpan_m () const
 183 {
 184     return layer_span;
 185 }
 186
 187 void
 188 SGCloudLayer::setSpan_m (float span_m)
 189 {
 190     if (span_m != layer_span) {
 191         layer_span = span_m;
 192         rebuild();
 193     }
 194 }
 195
 196 float
 197 SGCloudLayer::getElevation_m () const
 198 {
 199     return layer_asl;
 200 }
 201
 202 void
 203 SGCloudLayer::setElevation_m (float elevation_m, bool set_span)
 204 {
 205     layer_asl = elevation_m;
 206
 207     if (set_span) {
 208         if (elevation_m > 4000)
 209             setSpan_m(  elevation_m * 10 );
 210         else
 211             setSpan_m( 40000 );
 212     }
 213 }
 214
 215 float
 216 SGCloudLayer::getThickness_m () const
 217 {
 218     return layer_thickness;
 219 }
 220
 221 void
 222 SGCloudLayer::setThickness_m (float thickness_m)
 223 {
 224     layer_thickness = thickness_m;
 225 }
 226
 227 float
 228 SGCloudLayer::getTransition_m () const
 229 {
 230     return layer_transition;
 231 }
 232
 233 void
 234 SGCloudLayer::setTransition_m (float transition_m)
 235 {
 236     layer_transition = transition_m;
 237 }
 238
 239 SGCloudLayer::Coverage
 240 SGCloudLayer::getCoverage () const
 241 {
 242     return layer_coverage;
 243 }
 244
 245 void
 246 SGCloudLayer::setCoverage (Coverage coverage)
 247 {
 248     if (coverage != layer_coverage) {
 249         layer_coverage = coverage;
 250         rebuild();
 251     }
 252 }
 253
 254 void
 255 SGCloudLayer::setTextureOffset(const osg::Vec2& offset)
 256 {
 257     osg::StateAttribute* attr = layer_root->getStateSet()
 258         ->getTextureAttribute(0, osg::StateAttribute::TEXMAT);
 259     osg::TexMat* texMat = dynamic_cast<osg::TexMat*>(attr);
 260     if (!texMat)
 261         return;
 262     texMat->setMatrix(osg::Matrix::translate(offset[0], offset[1], 0.0));
 263 }
 264
 265 // build the cloud object
 266 void
 267 SGCloudLayer::rebuild()
 268 {
 269     // Initialize states and sizes if necessary.
 270     if ( !state_initialized ) {
 271         state_initialized = true;
 272
 273         SG_LOG(SG_ASTRO, SG_INFO, "initializing cloud layers");
 274
 275         osg::Texture::Extensions* extensions;
 276         extensions = osg::Texture::getExtensions(0, true);
 277         // OSGFIXME
 278         bump_mapping = extensions->isMultiTexturingSupported() &&
 279           (2 <= extensions->numTextureUnits()) &&
 280           SGIsOpenGLExtensionSupported("GL_ARB_texture_env_combine") &&
 281           SGIsOpenGLExtensionSupported("GL_ARB_texture_env_dot3");
 282
 283         osg::TextureCubeMap::Extensions* extensions2;
 284         extensions2 = osg::TextureCubeMap::getExtensions(0, true);
 285         bump_mapping = bump_mapping && extensions2->isCubeMapSupported();
 286
 287         // This bump mapping code was inspired by the tutorial available at
 288         // http://www.paulsprojects.net/tutorials/simplebump/simplebump.html
 289         // and a NVidia white paper
 290         //  http://developer.nvidia.com/object/bumpmappingwithregistercombiners.html
 291         // The normal map textures were generated by the normal map Gimp plugin :
 292         //  http://nifelheim.dyndns.org/~cocidius/normalmap/
 293         //
 294         cubeMap = new osg::TextureCubeMap;
 295         cubeMap->setFilter(osg::Texture::MIN_FILTER, osg::Texture::LINEAR);
 296         cubeMap->setFilter(osg::Texture::MAG_FILTER, osg::Texture::LINEAR);
 297         cubeMap->setWrap(osg::Texture::WRAP_S, osg::Texture::CLAMP_TO_EDGE);
 298         cubeMap->setWrap(osg::Texture::WRAP_T, osg::Texture::CLAMP_TO_EDGE);
 299         cubeMap->setWrap(osg::Texture::WRAP_R, osg::Texture::CLAMP_TO_EDGE);
 300
 301         const int size = 32;
 302         const float half_size = 16.0f;
 303         const float offset = 0.5f;
 304         osg::Vec3 zero_normal(0.5, 0.5, 0.5);
 305
 306         osg::Image* image = new osg::Image;
 307         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 308         unsigned char *ptr = image->data(0, 0);
 309         for (int j = 0; j < size; j++ ) {
 310           for (int i = 0; i < size; i++ ) {
 311             osg::Vec3 tmp(half_size, -( j + offset - half_size ),
 312                           -( i + offset - half_size ) );
 313             tmp.normalize();
 314             tmp = tmp*0.5 - zero_normal;
 315
 316             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 317             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 318             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 319           }
 320         }
 321         cubeMap->setImage(osg::TextureCubeMap::POSITIVE_X, image);
 322
 323         image = new osg::Image;
 324         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 325         ptr = image->data(0, 0);
 326         for (int j = 0; j < size; j++ ) {
 327           for (int i = 0; i < size; i++ ) {
 328             osg::Vec3 tmp(-half_size, -( j + offset - half_size ),
 329                           ( i + offset - half_size ) );
 330             tmp.normalize();
 331             tmp = tmp*0.5 - zero_normal;
 332
 333             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 334             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 335             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 336           }
 337         }
 338         cubeMap->setImage(osg::TextureCubeMap::NEGATIVE_X, image);
 339
 340         image = new osg::Image;
 341         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 342         ptr = image->data(0, 0);
 343         for (int j = 0; j < size; j++ ) {
 344           for (int i = 0; i < size; i++ ) {
 345             osg::Vec3 tmp(( i + offset - half_size ), half_size,
 346                           ( j + offset - half_size ) );
 347             tmp.normalize();
 348             tmp = tmp*0.5 - zero_normal;
 349
 350             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 351             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 352             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 353           }
 354         }
 355         cubeMap->setImage(osg::TextureCubeMap::POSITIVE_Y, image);
 356
 357         image = new osg::Image;
 358         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 359         ptr = image->data(0, 0);
 360         for (int j = 0; j < size; j++ ) {
 361           for (int i = 0; i < size; i++ ) {
 362             osg::Vec3 tmp(( i + offset - half_size ), -half_size,
 363                           -( j + offset - half_size ) );
 364             tmp.normalize();
 365             tmp = tmp*0.5 - zero_normal;
 366
 367             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 368             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 369             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 370           }
 371         }
 372         cubeMap->setImage(osg::TextureCubeMap::NEGATIVE_Y, image);
 373
 374         image = new osg::Image;
 375         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 376         ptr = image->data(0, 0);
 377         for (int j = 0; j < size; j++ ) {
 378           for (int i = 0; i < size; i++ ) {
 379             osg::Vec3 tmp(( i + offset - half_size ),
 380                           -( j + offset - half_size ), half_size );
 381             tmp.normalize();
 382             tmp = tmp*0.5 - zero_normal;
 383
 384             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 385             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 386             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 387           }
 388         }
 389         cubeMap->setImage(osg::TextureCubeMap::POSITIVE_Z, image);
 390
 391         image = new osg::Image;
 392         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 393         ptr = image->data(0, 0);
 394         for (int j = 0; j < size; j++ ) {
 395           for (int i = 0; i < size; i++ ) {
 396             osg::Vec3 tmp(-( i + offset - half_size ),
 397                           -( j + offset - half_size ), -half_size );
 398             tmp.normalize();
 399             tmp = tmp*0.5 - zero_normal;
 400             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 401             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 402             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 403           }
 404         }
 405         cubeMap->setImage(osg::TextureCubeMap::NEGATIVE_Z, image);
 406
 407         osg::StateSet* state;
 408         state = SGMakeState(texture_path, "overcast.rgb", "overcast_n.rgb");
 409         layer_states[SG_CLOUD_OVERCAST] = state;
 410         state = SGMakeState(texture_path, "overcast_top.rgb", "overcast_top_n.rgb");
 411         layer_states2[SG_CLOUD_OVERCAST] = state;
 412
 413         state = SGMakeState(texture_path, "broken.rgba", "broken_n.rgb");
 414         layer_states[SG_CLOUD_BROKEN] = state;
 415         layer_states2[SG_CLOUD_BROKEN] = state;
 416
 417         state = SGMakeState(texture_path, "scattered.rgba", "scattered_n.rgb");
 418         layer_states[SG_CLOUD_SCATTERED] = state;
 419         layer_states2[SG_CLOUD_SCATTERED] = state;
 420
 421         state = SGMakeState(texture_path, "few.rgba", "few_n.rgb");
 422         layer_states[SG_CLOUD_FEW] = state;
 423         layer_states2[SG_CLOUD_FEW] = state;
 424
 425         state = SGMakeState(texture_path, "cirrus.rgba", "cirrus_n.rgb");
 426         layer_states[SG_CLOUD_CIRRUS] = state;
 427         layer_states2[SG_CLOUD_CIRRUS] = state;
 428
 429         layer_states[SG_CLOUD_CLEAR] = 0;
 430         layer_states2[SG_CLOUD_CLEAR] = 0;
 431
 432       // OSGFIXME
 433 //              SGNewCloud::loadTextures(texture_path.str());
 434 //              layer3D->buildTestLayer();
 435     }
 436
 437     scale = 4000.0;
 438     last_lon = last_lat = -999.0f;
 439
 440     setTextureOffset(base);
 441     // build the cloud layer
 442     const float layer_scale = layer_span / scale;
 443     const float mpi = SG_PI/4;
 444
 445     // caclculate the difference between a flat-earth model and
 446     // a round earth model given the span and altutude ASL of
 447     // the cloud layer. This is the difference in altitude between
 448     // the top of the inverted bowl and the edge of the bowl.
 449     // const float alt_diff = layer_asl * 0.8;
 450     const float layer_to_core = (SG_EARTH_RAD * 1000 + layer_asl);
 451     const float layer_angle = 0.5*layer_span / layer_to_core; // The angle is half the span
 452     const float border_to_core = layer_to_core * cos(layer_angle);
 453     const float alt_diff = layer_to_core - border_to_core;
 454
 455     for (int i = 0; i < 4; i++) {
 456       if ( layer[i] != NULL ) {
 457         layer_transform->removeChild(layer[i].get()); // automatic delete
 458       }
 459
 460       vl[i] = new osg::Vec3Array;
 461       cl[i] = new osg::Vec4Array;
 462       tl[i] = new osg::Vec2Array;
 463
 464
 465       osg::Vec3 vertex(layer_span*(i-2)/2, -layer_span,
 466                        alt_diff * (sin(i*mpi) - 2));
 467       osg::Vec2 tc(layer_scale * i/4, 0.0f);
 468       osg::Vec4 color(1.0f, 1.0f, 1.0f, (i == 0) ? 0.0f : 0.15f);
 469
 470       cl[i]->push_back(color);
 471       vl[i]->push_back(vertex);
 472       tl[i]->push_back(tc);
 473
 474       for (int j = 0; j < 4; j++) {
 475         vertex = osg::Vec3(layer_span*(i-1)/2, layer_span*(j-2)/2,
 476                            alt_diff * (sin((i+1)*mpi) + sin(j*mpi) - 2));
 477         tc = osg::Vec2(layer_scale * (i+1)/4, layer_scale * j/4);
 478         color = osg::Vec4(1.0f, 1.0f, 1.0f,
 479                           ( (j == 0) || (i == 3)) ?
 480                           ( (j == 0) && (i == 3)) ? 0.0f : 0.15f : 1.0f );
 481
 482         cl[i]->push_back(color);
 483         vl[i]->push_back(vertex);
 484         tl[i]->push_back(tc);
 485
 486         vertex = osg::Vec3(layer_span*(i-2)/2, layer_span*(j-1)/2,
 487                            alt_diff * (sin(i*mpi) + sin((j+1)*mpi) - 2) );
 488         tc = osg::Vec2(layer_scale * i/4, layer_scale * (j+1)/4 );
 489         color = osg::Vec4(1.0f, 1.0f, 1.0f,
 490                           ((j == 3) || (i == 0)) ?
 491                           ((j == 3) && (i == 0)) ? 0.0f : 0.15f : 1.0f );
 492         cl[i]->push_back(color);
 493         vl[i]->push_back(vertex);
 494         tl[i]->push_back(tc);
 495       }
 496
 497       vertex = osg::Vec3(layer_span*(i-1)/2, layer_span,
 498                          alt_diff * (sin((i+1)*mpi) - 2));
 499
 500       tc = osg::Vec2(layer_scale * (i+1)/4, layer_scale);
 501
 502       color = osg::Vec4(1.0f, 1.0f, 1.0f, (i == 3) ? 0.0f : 0.15f );
 503
 504       cl[i]->push_back( color );
 505       vl[i]->push_back( vertex );
 506       tl[i]->push_back( tc );
 507
 508       osg::Geometry* geometry = new osg::Geometry;
 509       geometry->setUseDisplayList(false);
 510       geometry->setVertexArray(vl[i].get());
 511       geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 512       geometry->setColorArray(cl[i].get());
 513       geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 514       geometry->setTexCoordArray(0, tl[i].get());
 515       geometry->addPrimitiveSet(new osg::DrawArrays(GL_TRIANGLE_STRIP, 0, vl[i]->size()));
 516       layer[i] = new osg::Geode;
 517
 518       std::stringstream sstr;
 519       sstr << "Cloud Layer (" << i << ")";
 520       geometry->setName(sstr.str());
 521       layer[i]->setName(sstr.str());
 522       layer[i]->addDrawable(geometry);
 523       layer_transform->addChild(layer[i].get());
 524     }
 525
 526     //OSGFIXME: true
 527     if ( layer_states[layer_coverage].valid() ) {
 528       osg::CopyOp copyOp(osg::CopyOp::DEEP_COPY_ALL
 529                          & ~osg::CopyOp::DEEP_COPY_TEXTURES);
 530       // render bin will be set in reposition
 531       osg::StateSet* stateSet = static_cast<osg::StateSet*>(layer_states2[layer_coverage]->clone(copyOp));
 532       stateSet->setDataVariance(osg::Object::DYNAMIC);
 533       group_top->setStateSet(stateSet);
 534       stateSet = static_cast<osg::StateSet*>(layer_states2[layer_coverage]->clone(copyOp));
 535       stateSet->setDataVariance(osg::Object::DYNAMIC);
 536       group_bottom->setStateSet(stateSet);
 537     }
 538 }
 539
 540 #if 0
 541             sgMat4 modelview,
 542                    tmp,
 543                    transform;
 544             ssgGetModelviewMatrix( modelview );
 545             layer_transform->getTransform( transform );
 546
 547             sgTransposeNegateMat4( tmp, transform );
 548
 549             sgPostMultMat4( transform, modelview );
 550             ssgLoadModelviewMatrix( transform );
 551
 552             sgVec3 lightVec;
 553             ssgGetLight( 0 )->getPosition( lightVec );
 554             sgNegateVec3( lightVec );
 555             sgXformVec3( lightVec, tmp );
 556
 557             for ( int i = 0; i < 25; i++ ) {
 558                 CloudVertex &v = vertices[ i ];
 559                 sgSetVec3( v.tangentSpLight,
 560                            sgScalarProductVec3( v.sTangent, lightVec ),
 561                            sgScalarProductVec3( v.tTangent, lightVec ),
 562                            sgScalarProductVec3( v.normal, lightVec ) );
 563             }
 564
 565             ssgTexture *decal = color_map[ layer_coverage ][ top ? 1 : 0 ];
 566             if ( top && decal == 0 ) {
 567                 decal = color_map[ layer_coverage ][ 0 ];
 568             }
 569             ssgTexture *normal = normal_map[ layer_coverage ][ top ? 1 : 0 ];
 570             if ( top && normal == 0 ) {
 571                 normal = normal_map[ layer_coverage ][ 0 ];
 572             }
 573
 574             glDisable( GL_LIGHTING );
 575             glDisable( GL_CULL_FACE );
 576 //            glDisable( GL_ALPHA_TEST );
 577             if ( layer_coverage == SG_CLOUD_FEW ) {
 578                 glEnable( GL_ALPHA_TEST );
 579                 glAlphaFunc ( GL_GREATER, 0.01 );
 580             }
 581             glEnable( GL_BLEND );
 582             glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA );
 583
 584             glShadeModel( GL_SMOOTH );
 585             glEnable( GL_COLOR_MATERIAL );
 586             sgVec4 color;
 587             float emis = 0.05;
 588             if ( 1 ) {
 589                 ssgGetLight( 0 )->getColour( GL_DIFFUSE, color );
 590                 emis = ( color[0]+color[1]+color[2] ) / 3.0;
 591                 if ( emis < 0.05 )
 592                     emis = 0.05;
 593             }
 594             sgSetVec4( color, emis, emis, emis, 0.0 );
 595             glMaterialfv( GL_FRONT_AND_BACK, GL_EMISSION, color );
 596             sgSetVec4( color, 1.0f, 1.0f, 1.0f, 0.0 );
 597             glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT, color );
 598             sgSetVec4( color, 1.0, 1.0, 1.0, 0.0 );
 599             glMaterialfv( GL_FRONT_AND_BACK, GL_DIFFUSE, color );
 600             sgSetVec4( color, 0.0, 0.0, 0.0, 0.0 );
 601             glMaterialfv( GL_FRONT_AND_BACK, GL_SPECULAR, color );
 602
 603             glColor4f( 1.0f, 1.0f, 1.0f, 1.0f );
 604
 605             glActiveTexturePtr( GL_TEXTURE0_ARB );
 606             glBindTexture( GL_TEXTURE_2D, normal->getHandle() );
 607             glEnable( GL_TEXTURE_2D );
 608
 609             //Bind normalisation cube map to texture unit 1
 610             glActiveTexturePtr( GL_TEXTURE1_ARB );
 611             glBindTexture( GL_TEXTURE_CUBE_MAP_ARB, normalization_cube_map );
 612             glEnable( GL_TEXTURE_CUBE_MAP_ARB );
 613             glActiveTexturePtr( GL_TEXTURE0_ARB );
 614
 615             //Set vertex arrays for cloud
 616             glVertexPointer( 3, GL_FLOAT, sizeof(CloudVertex), &vertices[0].position );
 617             glEnableClientState( GL_VERTEX_ARRAY );
 618 /*
 619             if ( nb_texture_unit >= 3 ) {
 620                 glColorPointer( 4, GL_FLOAT, sizeof(CloudVertex), &vertices[0].color );
 621                 glEnableClientState( GL_COLOR_ARRAY );
 622             }
 623 */
 624             //Send texture coords for normal map to unit 0
 625             glTexCoordPointer( 2, GL_FLOAT, sizeof(CloudVertex), &vertices[0].texCoord );
 626             glEnableClientState( GL_TEXTURE_COORD_ARRAY );
 627
 628             //Send tangent space light vectors for normalisation to unit 1
 629             glClientActiveTexturePtr( GL_TEXTURE1_ARB );
 630             glTexCoordPointer( 3, GL_FLOAT, sizeof(CloudVertex), &vertices[0].tangentSpLight );
 631             glEnableClientState( GL_TEXTURE_COORD_ARRAY );
 632
 633             //Set up texture environment to do (tex0 dot tex1)*color
 634             glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB );
 635             glTexEnvi( GL_TEXTURE_ENV, GL_SOURCE0_RGB_ARB, GL_TEXTURE );
 636             glTexEnvi( GL_TEXTURE_ENV, GL_COMBINE_RGB_ARB, GL_REPLACE );
 637             glTexEnvi( GL_TEXTURE_ENV, GL_SOURCE0_ALPHA_ARB, GL_TEXTURE );
 638             glTexEnvi( GL_TEXTURE_ENV, GL_COMBINE_ALPHA_ARB, GL_REPLACE );
 639
 640 // use TexEnvCombine to add the highlights to the original lighting
 641 osg::TexEnvCombine *te = new osg::TexEnvCombine;
 642 te->setSource0_RGB(osg::TexEnvCombine::TEXTURE);
 643 te->setCombine_RGB(osg::TexEnvCombine::REPLACE);
 644 te->setSource0_Alpha(osg::TexEnvCombine::TEXTURE);
 645 te->setCombine_Alpha(osg::TexEnvCombine::REPLACE);
 646 ss->setTextureAttributeAndModes(0, te, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
 647
 648
 649             glActiveTexturePtr( GL_TEXTURE1_ARB );
 650
 651             glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB );
 652             glTexEnvi( GL_TEXTURE_ENV, GL_SOURCE0_RGB_ARB, GL_TEXTURE );
 653             glTexEnvi( GL_TEXTURE_ENV, GL_COMBINE_RGB_ARB, GL_DOT3_RGB_ARB );
 654             glTexEnvi( GL_TEXTURE_ENV, GL_SOURCE1_RGB_ARB, GL_PREVIOUS_ARB );
 655             glTexEnvi( GL_TEXTURE_ENV, GL_SOURCE0_ALPHA_ARB, GL_PREVIOUS_ARB );
 656             glTexEnvi( GL_TEXTURE_ENV, GL_COMBINE_ALPHA_ARB, GL_REPLACE );
 657
 658 osg::TexEnvCombine *te = new osg::TexEnvCombine;
 659 te->setSource0_RGB(osg::TexEnvCombine::TEXTURE);
 660 te->setCombine_RGB(osg::TexEnvCombine::DOT3_RGB);
 661 te->setSource1_RGB(osg::TexEnvCombine::PREVIOUS);
 662 te->setSource0_Alpha(osg::TexEnvCombine::PREVIOUS);
 663 te->setCombine_Alpha(osg::TexEnvCombine::REPLACE);
 664 ss->setTextureAttributeAndModes(0, te, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
 665
 666
 667             if ( nb_texture_unit >= 3 ) {
 668                 glActiveTexturePtr( GL_TEXTURE2_ARB );
 669                 glBindTexture( GL_TEXTURE_2D, decal->getHandle() );
 670
 671                 glClientActiveTexturePtr( GL_TEXTURE2_ARB );
 672                 glTexCoordPointer( 2, GL_FLOAT, sizeof(CloudVertex), &vertices[0].texCoord );
 673                 glEnableClientState( GL_TEXTURE_COORD_ARRAY );
 674
 675                 glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB );
 676                 glTexEnvi( GL_TEXTURE_ENV, GL_COMBINE_RGB_ARB, GL_ADD );
 677                 glTexEnvi( GL_TEXTURE_ENV, GL_SOURCE0_RGB_ARB, GL_TEXTURE );
 678                 glTexEnvi( GL_TEXTURE_ENV, GL_SOURCE1_RGB_ARB, GL_PREVIOUS_ARB );
 679
 680                 glClientActiveTexturePtr( GL_TEXTURE0_ARB );
 681                 glActiveTexturePtr( GL_TEXTURE0_ARB );
 682
 683                 //Draw cloud layer
 684                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[0] );
 685                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[10] );
 686                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[20] );
 687                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[30] );
 688
 689                 glDisable( GL_TEXTURE_2D );
 690                 glActiveTexturePtr( GL_TEXTURE1_ARB );
 691                 glDisable( GL_TEXTURE_CUBE_MAP_ARB );
 692                 glActiveTexturePtr( GL_TEXTURE2_ARB );
 693                 glDisable( GL_TEXTURE_2D );
 694                 glActiveTexturePtr( GL_TEXTURE0_ARB );
 695
 696                 glDisableClientState( GL_TEXTURE_COORD_ARRAY );
 697                 glClientActiveTexturePtr( GL_TEXTURE1_ARB );
 698                 glDisableClientState( GL_TEXTURE_COORD_ARRAY );
 699                 glClientActiveTexturePtr( GL_TEXTURE2_ARB );
 700                 glDisableClientState( GL_TEXTURE_COORD_ARRAY );
 701                 glClientActiveTexturePtr( GL_TEXTURE0_ARB );
 702
 703                 glDisableClientState( GL_COLOR_ARRAY );
 704                 glEnable( GL_LIGHTING );
 705
 706                 glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE );
 707
 708             } else {
 709                 glClientActiveTexturePtr( GL_TEXTURE0_ARB );
 710                 glActiveTexturePtr( GL_TEXTURE0_ARB );
 711
 712                 //Draw cloud layer
 713                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[0] );
 714                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[10] );
 715                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[20] );
 716                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[30] );
 717
 718                 //Disable textures
 719                 glDisable( GL_TEXTURE_2D );
 720
 721                 glActiveTexturePtr( GL_TEXTURE1_ARB );
 722                 glDisable( GL_TEXTURE_CUBE_MAP_ARB );
 723                 glActiveTexturePtr( GL_TEXTURE0_ARB );
 724
 725                 //disable vertex arrays
 726                 glDisableClientState( GL_VERTEX_ARRAY );
 727
 728                 glDisableClientState( GL_TEXTURE_COORD_ARRAY );
 729                 glClientActiveTexturePtr( GL_TEXTURE1_ARB );
 730                 glDisableClientState( GL_TEXTURE_COORD_ARRAY );
 731                 glClientActiveTexturePtr( GL_TEXTURE0_ARB );
 732
 733                 //Return to standard modulate texenv
 734                 glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE );
 735
 736                 if ( layer_coverage == SG_CLOUD_OVERCAST ) {
 737                     glDepthFunc(GL_LEQUAL);
 738
 739                     glEnable( GL_LIGHTING );
 740                     sgVec4 color;
 741                     ssgGetLight( 0 )->getColour( GL_DIFFUSE, color );
 742                     float average = ( color[0] + color[1] + color[2] ) / 3.0f;
 743                     average = 0.15 + average/10;
 744                     sgVec4 averageColor;
 745                     sgSetVec4( averageColor, average, average, average, 1.0f );
 746                     ssgGetLight( 0 )->setColour( GL_DIFFUSE, averageColor );
 747
 748                     glBlendColorPtr( average, average, average, 1.0f );
 749                     glBlendFunc( GL_ONE_MINUS_CONSTANT_COLOR, GL_CONSTANT_COLOR );
 750
 751                     //Perform a second pass to color the torus
 752                     //Bind decal texture
 753                     glBindTexture( GL_TEXTURE_2D, decal->getHandle() );
 754                     glEnable(GL_TEXTURE_2D);
 755
 756                     //Set vertex arrays for torus
 757                     glVertexPointer( 3, GL_FLOAT, sizeof(CloudVertex), &vertices[0].position );
 758                     glEnableClientState( GL_VERTEX_ARRAY );
 759
 760                     //glColorPointer( 4, GL_FLOAT, sizeof(CloudVertex), &vertices[0].color );
 761                     //glEnableClientState( GL_COLOR_ARRAY );
 762
 763                     glNormalPointer( GL_FLOAT, sizeof(CloudVertex), &vertices[0].normal );
 764                     glEnableClientState( GL_NORMAL_ARRAY );
 765
 766                     glTexCoordPointer( 2, GL_FLOAT, sizeof(CloudVertex), &vertices[0].texCoord );
 767                     glEnableClientState( GL_TEXTURE_COORD_ARRAY );
 768
 769                     //Draw cloud layer
 770                     glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[0] );
 771                     glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[10] );
 772                     glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[20] );
 773                     glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[30] );
 774
 775                     ssgGetLight( 0 )->setColour( GL_DIFFUSE, color );
 776
 777                     glDisableClientState( GL_TEXTURE_COORD_ARRAY );
 778                 }
 779             }
 780             //Disable texture
 781             glDisable( GL_TEXTURE_2D );
 782
 783             glDisableClientState( GL_VERTEX_ARRAY );
 784             glDisableClientState( GL_NORMAL_ARRAY );
 785
 786             glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA );
 787             glEnable( GL_CULL_FACE );
 788             glDepthFunc(GL_LESS);
 789
 790             ssgLoadModelviewMatrix( modelview );
 791 #endif
 792
 793 // repaint the cloud layer colors
 794 bool SGCloudLayer::repaint( const SGVec3f& fog_color ) {
 795   for ( int i = 0; i < 4; i++ ) {
 796     osg::Vec4 color(fog_color.osg(), 1);
 797     color[3] = (i == 0) ? 0.0f : cloud_alpha * 0.15f;
 798     (*cl[i])[0] = color;
 799
 800     for ( int j = 0; j < 4; ++j ) {
 801       color[3] =
 802         ((j == 0) || (i == 3)) ?
 803         ((j == 0) && (i == 3)) ? 0.0f : cloud_alpha * 0.15f : cloud_alpha;
 804       (*cl[i])[(2*j) + 1] = color;
 805
 806       color[3] =
 807         ((j == 3) || (i == 0)) ?
 808         ((j == 3) && (i == 0)) ? 0.0f : cloud_alpha * 0.15f : cloud_alpha;
 809       (*cl[i])[(2*j) + 2] = color;
 810     }
 811
 812     color[3] = (i == 3) ? 0.0f : cloud_alpha * 0.15f;
 813     (*cl[i])[9] = color;
 814
 815     cl[i]->dirty();
 816   }
 817
 818   return true;
 819 }
 820
 821 // reposition the cloud layer at the specified origin and orientation
 822 // lon specifies a rotation about the Z axis
 823 // lat specifies a rotation about the new Y axis
 824 // spin specifies a rotation about the new Z axis (and orients the
 825 // sunrise/set effects
 826 bool SGCloudLayer::reposition( const SGVec3f& p, const SGVec3f& up, double lon, double lat,
 827                                double alt, double dt )
 828 {
 829     // combine p and asl (meters) to get translation offset
 830     osg::Vec3 asl_offset(up.osg());
 831     asl_offset.normalize();
 832     if ( alt <= layer_asl ) {
 833         asl_offset *= layer_asl;
 834     } else {
 835         asl_offset *= layer_asl + layer_thickness;
 836     }
 837
 838     // cout << "asl_offset = " << asl_offset[0] << "," << asl_offset[1]
 839     //      << "," << asl_offset[2] << endl;
 840     asl_offset += p.osg();
 841     // cout << "  asl_offset = " << asl_offset[0] << "," << asl_offset[1]
 842     //      << "," << asl_offset[2] << endl;
 843
 844     osg::Matrix T, LON, LAT;
 845     // Translate to zero elevation
 846     // Point3D zero_elev = current_view.get_cur_zero_elev();
 847     T.makeTranslate( asl_offset );
 848
 849     // printf("  Translated to %.2f %.2f %.2f\n",
 850     //        zero_elev.x, zero_elev.y, zero_elev.z );
 851
 852     // Rotate to proper orientation
 853     // printf("  lon = %.2f  lat = %.2f\n",
 854     //        lon * SGD_RADIANS_TO_DEGREES,
 855     //        lat * SGD_RADIANS_TO_DEGREES);
 856     LON.makeRotate(lon, osg::Vec3(0, 0, 1));
 857
 858     // xglRotatef( 90.0 - f->get_Latitude() * SGD_RADIANS_TO_DEGREES,
 859     //             0.0, 1.0, 0.0 );
 860     LAT.makeRotate(90.0 * SGD_DEGREES_TO_RADIANS - lat, osg::Vec3(0, 1, 0));
 861
 862     layer_transform->setMatrix( LAT*LON*T );
 863     // The layers need to be drawn in order because they are
 864     // translucent, but OSG transparency sorting doesn't work because
 865     // the cloud polys are huge. However, the ordering is simple: the
 866     // bottom polys should be drawn from high altitude to low, and the
 867     // top polygons from low to high. The altitude can be used
 868     // directly to order the polygons!
 869     layer_root->getChild(0)->getStateSet()->setRenderBinDetails(-(int)layer_asl,
 870                                                                 "RenderBin");
 871     layer_root->getChild(1)->getStateSet()->setRenderBinDetails((int)layer_asl,
 872                                                                 "RenderBin");
 873     if ( alt <= layer_asl ) {
 874       layer_root->setSingleChildOn(0);
 875     } else if ( alt >= layer_asl + layer_thickness ) {
 876       layer_root->setSingleChildOn(1);
 877     } else {
 878       layer_root->setAllChildrenOff();
 879     }
 880
 881
 882     // now calculate update texture coordinates
 883     if ( last_lon < -900 ) {
 884         last_lon = lon;
 885         last_lat = lat;
 886     }
 887
 888     double sp_dist = speed*dt;
 889
 890     if ( lon != last_lon || lat != last_lat || sp_dist != 0 ) {
 891         Point3D start( last_lon, last_lat, 0.0 );
 892         Point3D dest( lon, lat, 0.0 );
 893         double course = 0.0, dist = 0.0;
 894
 895         calc_gc_course_dist( dest, start, &course, &dist );
 896         // cout << "course = " << course << ", dist = " << dist << endl;
 897
 898         // if start and dest are too close together,
 899         // calc_gc_course_dist() can return a course of "nan".  If
 900         // this happens, lets just use the last known good course.
 901         // This is a hack, and it would probably be better to make
 902         // calc_gc_course_dist() more robust.
 903         if ( isnan(course) ) {
 904             course = last_course;
 905         } else {
 906             last_course = course;
 907         }
 908
 909         // calculate cloud movement due to external forces
 910         double ax = 0.0, ay = 0.0, bx = 0.0, by = 0.0;
 911
 912         if (dist > 0.0) {
 913             ax = cos(course) * dist;
 914             ay = sin(course) * dist;
 915         }
 916
 917         if (sp_dist > 0) {
 918             bx = cos((180.0-direction) * SGD_DEGREES_TO_RADIANS) * sp_dist;
 919             by = sin((180.0-direction) * SGD_DEGREES_TO_RADIANS) * sp_dist;
 920         }
 921
 922
 923         double xoff = (ax + bx) / (2 * scale);
 924         double yoff = (ay + by) / (2 * scale);
 925
 926         const float layer_scale = layer_span / scale;
 927
 928         // cout << "xoff = " << xoff << ", yoff = " << yoff << endl;
 929         base[0] += xoff;
 930
 931         // the while loops can lead to *long* pauses if base[0] comes
 932         // with a bogus value.
 933         // while ( base[0] > 1.0 ) { base[0] -= 1.0; }
 934         // while ( base[0] < 0.0 ) { base[0] += 1.0; }
 935         if ( base[0] > -10.0 && base[0] < 10.0 ) {
 936             base[0] -= (int)base[0];
 937         } else {
 938             SG_LOG(SG_ASTRO, SG_DEBUG,
 939                 "Error: base = " << base[0] << "," << base[1] <<
 940                 " course = " << course << " dist = " << dist );
 941             base[0] = 0.0;
 942         }
 943
 944         base[1] += yoff;
 945         // the while loops can lead to *long* pauses if base[0] comes
 946         // with a bogus value.
 947         // while ( base[1] > 1.0 ) { base[1] -= 1.0; }
 948         // while ( base[1] < 0.0 ) { base[1] += 1.0; }
 949         if ( base[1] > -10.0 && base[1] < 10.0 ) {
 950             base[1] -= (int)base[1];
 951         } else {
 952             SG_LOG(SG_ASTRO, SG_DEBUG,
 953                     "Error: base = " << base[0] << "," << base[1] <<
 954                     " course = " << course << " dist = " << dist );
 955             base[1] = 0.0;
 956         }
 957
 958         // cout << "base = " << base[0] << "," << base[1] << endl;
 959
 960         setTextureOffset(base);
 961         last_lon = lon;
 962         last_lat = lat;
 963     }
 964
 965 //      layer3D->reposition( p, up, lon, lat, alt, dt, direction, speed);
 966     return true;
 967 }